Traditionally, a wide variety of ID cards, including personal identification certificates, driving licenses and membership certificates, have been used. The ID card usually bears a personal figure image four identifying the card owner and various records. The personal figure image can be prepared as a gradation information image because it usually has a density gradation. The various records include the address, name, date of birth and position of the card owner and the validation date of the card in the case of personal identification certificates, and the date of birth, name and license number of the card owner and the license category in the case of driving licenses. These records can be prepared as character information because they are usually written in characters, numerical figures, symbols, etc.
In recent years, ID cards prepared to have a gradation image formed by sublimation thermal transfer have been developed, since beautiful images can easily be formed. Sublimation thermal transfer is generally defined as the method by which a gradation image, such as a portrait image, is formed in the image-receiving layer by superposing the image-receiving layer of an image-receiving sheet formed on a support and the ink layer, containing a sublimation dye, of an ink sheet on a support and subjecting them to imagewise heating to diffuse and transfer the sublimation dye into the image-receiving layer.
The ID card also bears non-personal information shared by the same kind of ID cards issued in large numbers in characters, figures, symbols, etc. For example, in driving licenses, a kind of ID card, the gradation image as a portrait picture and the date of birth, name, etc. of the card owner are unique to the card owner, while the name of the public safety commission which has issued the driving license, ruled lines, frames, etc. are all common among all driving licenses of the same kind.
It is therefore very inefficient to form a gradation image as a portrait image, personal information of the card owner and information common to the licenses issued by the driving license issuer on the surface of the image-receiving layer formed on the support for each sheet of driving license. Since driving license issuers should quickly issue a large number of driving licenses at one time, there is demand for a method of quickly producing driving licenses.
ID cards, such as driving licenses, cannot serve for their essential purpose, if they permit easy forgery or alteration, such as exchanging the portrait picture and rewriting the recorded information.
In addition, it is essential to protect the card's face on which the portrait picture and information have been recorded by some means to provide the recorded image with durability under various sets of conditions.
However, the conventional laminate film type surface protecting method, which uses a thermoplastic resin as an adhesive, is faulty that heating adhesion is weak and curling is likely to occur upon hot pressing.
The present invention has been developed in the circumstances described above.
Accordingly, it is an object of the invention to provide an ID card which can be produces rapidly. It is another object of the invention to provide a method of rapidly producing an ID card.